SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bec4bb8e7d4445c5a438fc2e8beed82281608828828afdb4a31ca06042878fb' 
  AND token = 'gTYQqDEbFa8idvfhLXT9Xg95dc5sWQhVx9ip6o8nNxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}